If a profit were built into the potential, then it could be used to support the Fellows program for example.
C
This is a good thought, and it leads to a late idea: instead of photos of clients, how about photos of some Kiva fellows in the field, which depict their locations without showing identifiable clients? In fact, you could solicit them to sumbit photos of themselves, or photos that they have taken. I imagine this would make issues such as releases and copyright permission much more straightforward. Surely at least some of them would be willing to contribute their photos for such a project, and it could become a constant source of new photos for the future.
Hope this is helpful, even if so late.